That planet

You know, the one having a birthday? . . . the one that has the Roman name of a Greek god? . . . and makes little boys giggle? Oh, heck.

Two hundred and twenty years ago Tuesday, the British astronomer Frederick William Herschel discovered a foolproof way to make grade-school boys laugh.

He identified the seventh planet from the sun, the one that came to be named after the Greek god of the sky. It was a momentous day in astronomy (the rest of the planets, visible to the naked eye, had been known for many centuries) and, it turns out, an equally major event in the history of bathroom humor.

Since that day in 1781, many things have been ascertained about this bright blue disk, which in class pictures of the solar system is the third celestial body from the right.

"Oh, that planet," says Tom Burns, the director of the Perkins Observatory outside Columbus, Ohio. "The bane of my existence. I consider myself a tolerant guy, but am I supposed to laugh the ten thousandth time a third-grader asks me: 'Can I see your anus in the telescope?' "

Part of Burns' mission in life is to establish an accepted pronunciation for the planet located between Saturn and Neptune. For the record, he says, it's YOUR-uh-ness.

He's not getting total support from Webster's Dictionary, which lists the dreaded long-A pronunciation as equally acceptable. Clearly, Mr. Webster never observed what happens to a group of school children when they learn that a certain funny-sounding planet is surrounded by smelly gas.

But astronomers know. Their references to the planet whose orbit around the sun takes 84 years always include an earnest attempt at linguistic propriety:

YOU-rah-nus, YOU-raw-nis, yoo-RAY-nuhs and ER-a-nus, to name a few. If Thurston Howell III were an amateur astronomer, no doubt he'd pronounce it oo-RAH-nus.

The teachers at Bay Point Elementary, a science magnet school in St. Petersburg, take a looser, less dogmatic approach.

Fortunately for the teachers, in second grade, when the names of the planets are first introduced, there's enough of a lag between the children's anatomical and astronomical knowledge that they don't get the joke. They make up for it, Woolums says, in fourth grade.

"Then we nip it in the bud," he says.

None of this confusion would have ensued had Herschel been allowed to name his discovery.

Herschel originally proposed Georgium Sidus (George's Star) in honor of the reigning English monarch, George III. He was overruled by Johann Bode, the German astronomer who was something like the baseball commissioner of 18th-century stargazers. Bode insisted the naming follow the tradition of employing the Roman names of Greek gods.

No one quibbled with Mercury (Hermes), Venus (Aphrodite), Mars (Ares), Jupiter (Zeus) or Saturn (Kronos). The next logical god, Bode maintained, had to be Ouranos, who was Kronos' father.